Function ExecReScanIndexOnlyScan

src/backend/executor/nodeIndexonlyscan.c:332–360

---------------------------------------------------------------- * ExecReScanIndexOnlyScan(node) * * Recalculates the values of any scan keys whose value depends on * information known at runtime, then rescans the indexed relation. * * Updating the scan key was formerly done separately in * ExecUpdateIndexScanKeys. Integrating it into ReScan makes * rescans of indices and relations/g

 * ----------------------------------------------------------------
 */
void
ExecReScanIndexOnlyScan(IndexOnlyScanState *node)
{
	/*
	 * If we are doing runtime key calculations (ie, any of the index key
	 * values weren't simple Consts), compute the new key values.  But first,
	 * reset the context so we don't leak memory as each outer tuple is
	 * scanned.  Note this assumes that we will recalculate *all* runtime keys
	 * on each call.
	 */
	if (node->ioss_NumRuntimeKeys != 0)
	{
		ExprContext *econtext = node->ioss_RuntimeContext;

		ResetExprContext(econtext);
		ExecIndexEvalRuntimeKeys(econtext,
								 node->ioss_RuntimeKeys,
								 node->ioss_NumRuntimeKeys);
	}
	node->ioss_RuntimeKeysReady = true;

	/* reset index scan */
	if (node->ioss_ScanDesc)
		index_rescan(node->ioss_ScanDesc,
					 node->ioss_ScanKeys, node->ioss_NumScanKeys,
					 node->ioss_OrderByKeys, node->ioss_NumOrderByKeys);

	ExecScanReScan(&node->ss);
}


/* ----------------------------------------------------------------